Method of making printing designs.



UNITED STATES PAT T OFFICE.

GEORGE R. CORNWALL, OF PORT CHESTER, NEWV YORK.

METHOD OF MAKING PRINTING DESIGNS.

SPEGIFICATION forming part of Letters Patent No. 630,664, dated August 8,

Application filed November 27, 1897- To all whom, it may concern:

Be it'known that I, GEORGE R. CORNWALL, a citizen of the United States, residing at Port Chester, county of Westchester, and State of New York, have invented certain new and useful Improvementsin Methods of Making Printing Designs, of'which the following is a specification. v

V In a patent granted to me November 15, 1898, No. 614,090, for improvements in printing-machines I have claimed a machine comprising a series of designs or characters surrounded or outlined by ink-rejecting surfaces, a dampening device, an inking device, and means for impressing said printing designs or characters individually and independently against an impression receiving surface. v

The object of my present invention is to provide a simple and eifective method of producing printing designs or characters upon printing plates, type, &c.- suoh,forinstance,' as are claimed in said above-named patent.

My improved method of, producing print-- ing designs or characters consists in first cutting, stamping, or impressing the designs or characters into a sheet. or plate of aluminium or other suitable material, next coating said sheet or plate, including the depressed or cut designs or characters, with a film of ink-attracting substance, preferably asphaltum, then cutting, grinding, or etching the surface of the plate to such. an extent as to completely remove the ink-attracting material from all parts of the plate except from the depressed portions forming the'design, then treating the surface of the plate with a cleansing acid solution, such as dilute nitric acid, and finally subjecting the surface of the plate to an acid gum solution to render ink-rejecting the portions of the plate surrounding and outlining the design when moistened by a suitable dampening device. The sheet or plate of aluminium or other suitable material is preferably supported by a metal backingplate, but the latter may be omitted.

My invention is applicable to all kinds of printing where the design is formed by separate and distinct lines, stipples, grains, or othermarks; Thus it may withadvantage be used for type, script, and illustrative de- Serial No. 660,015. (No specimens.) g

signs and is especially adapted to the reproduction of engraved designs.

In applying my invention to the formation or reproduction of type I proceed as follows: A surface, film, or plate of aluminium is formed or attached to a backing of iron or other suitable metal. Type designs are engraved or arestamped by suitable dies into the aluminium. The plate is now sufficiently flooded or coated with a solution of asphaltum to film the design, and the asphaltum is then dried. The surface of the plateis now cut away or removed to an extent sufficient to remove all the asphaltum from the nude pressed parts of the plate, while leaving the depressed portion only covered with asphaltum, thus bringing out the design. This may-be done by grinding the plate with any suitable abradeut, such as pumice, applied with any suitable block. The plate is now treated with moderately dilute nitric acid, which removes from the surface of the metal any ink-attracting impurities, and, finally,

after'washing with water and drying the plate is treated with an acid gum solution consisting of gum-arabic, phosphoric acid, and Water. in usual proportions. Thereby the type designs in ink-attracting material 7 are surrounded by a surface which is adapted to take'moisture from a dampening device and to act as an ink-rejecting surface. The plateis then out up by sawing or otherwise into such shapes as may be most convenient to handle-for example, into separate type.

For making script designs 'I prefer to proceed as follows: A set of dies adapted to form by stamping the letters desired are provided, and after stamping the letters into the plate in the desired positions the lettering is completed and finishedby hand-engraving. The plate with the depressed design thus formed therein is then subjected to the same treatment as above described for the formation of typeletters, except that i in this the plate would not in general be cut up.

For illustrative work the design would be engraved directly on the plate or be sunken or depressed therein by the use of the usual transfer rolls or dies now used in steel-plate reproductions. The plate is then treated by the method described above.

The surface of the plate is in any case cut away sufficiently to bring out thedesign, as above stated; but the design may be left in a condition of either slight relief or in the same plane with the surrounding surface or in intaglio, according to the character of the subject and the character of the medium on which the printing is to be done.

If the design is to be on the same plane as the surrounding surface, the plate is simply ground or etched away till the surfaces of the design and of the rest of the plate are coincident. If the design is to be in intaglio, the film of asphalt applied should be quite thin so as not to fill the depressions, and the cutting away of the plate would be stopped at such a point as to still leave the design with its asphalt lining depressed below the rest of the plate. If the design is to be in relief, the plate after being ground down to bring out the designs and surrounding portions into one plane is subjected to an etching agent, such as hydrochloric acid, which will cut away or depress the said surrounding portions leaving the design in slight relief. The printing designs or characters thus prepared are applicable for printing in any printing-machine equipped with a dampening device.

' The advantages of myinvention lie mainly in the fact that it enables the cheap and rapid reproduction of printing designs from original engraved characters or designs, while conserving to the fullest extent their sharpness and clearness of outline, a desideratum which is not attainable by the usual methods of transfer.

A further advantage with especial reference to script-work is the rapid and cheap manner in which a script design may be produced by the use of character-dies, thus dispensing with practically all of the laborious and expensive hand or machine engraving heretofore necessary.

Vhile I prefer to apply the film of ink-attracting material to the plate after the design has been impressed therein, it might in some cases be applied to the plate in the first place, the stamping or cutting being then effected and the depressed portions then, if necessary, being again coated with the ink-attracting material.

Having thus fully described my invention, the following is What I claim as new therein and desire to secure by Letters Patent:

1. The herewith-described method of producing printing designs consisting in forming an intaglio design in the surface of a plate, applying a film of ink-attracting material directly to the plate including both the design and the intermediate portions, removing the inkattracting material to the level of the surface of the plate surrounding the designs or characters so as to expose such surface, and finally treating said surrounding exposed surface of the plate to render it ink-rejecting.

2. The herewith-described method of producing printing designs consisting in forming in the surface of a plate, a depressed design, applying to the plate including the design a film of ink-attracting material, then removing the surface of the plate so as to remove the ink-attracting material from the parts of the plate surrounding the design while leaving it in the parts occupied by the design and finally treating the exposed surface of the plate surrounding the design to render it ink-rejecting.

3. The herewith-described method of-producing printing designs, consisting in forming a depressed design in the surface of a metal plate, then coating the plate, including the design, with a film of asphaltum, then removing the surface of the plate so as to remove the asphaltum from the parts of the plate surrounding the design, and finally treating the exposed surface of the plate, surrounding the design, to renderit ink-rejecting.

4:- The herewith-desoribed method of producing printing designs, consisting in forming a depressed design in the surface of a metal plate, then coating the plate, including the design, with a film of asphaltum, then removing the surface of the plate so as to remove the asphaltum from the parts of the plate surrounding the design, then cleaning this exposed surface by suitable agent such as nitric acid, and finally treating the exposed surface surrounding the design with an acid gum solution to render it ink-rejectin g.

GEO. R. CORNWALL.

Witnesses:

M. V. BIDGOOD, FREDK. IIANDRICK. 

